70 CHAPTER 5 Prescription of antithrombotic therapy During the entire study period, most patients were prescribed VKA monotherapy, with a decline from 46.7% in 2008 to 41.3% in 2017 (see Figure 2). The percentage of patients who were prescribed NOAC monotherapy steadily increased, from 0.0% in 2011 to 19.5% in 2017. Most of the 1,608 AF patients who were prescribed NOAC monotherapy for the first time during the study period, were new-onset AF patients (57.4%). The percentage of patients with a diagnostic code for AF and with a CHA2DS2VASc score ≥2 (justifying OAC therapy for stroke prevention) who were not prescribed OAC therapy decreased from 42.2% in 2008 (consisting of 15.3% who were prescribed platelet inhibitor monotherapy and 26.9% who were prescribed no antithrombotic therapy at all) to 25.4% in 2017 (8.5% were prescribed platelet inhibitor monotherapy and 16.9% were not prescribed any antithrombotic therapy). FIGURE 2: TRENDS IN ANTITHROMBOTIC PRESCRIPTIONS IN ALL PATIENTS WITH ATRIAL FIBRILLATION IN PRIMARY CARE. NOAC: non-vitamin K antagonist oral anticoagulant; PI: platelet inhibitor; VKA: vitamin K antagonist. Selective anticoagulant prescription In univariable logistic regression analyses, each predefined patient characteristic might be related to VKA prescription rather than NOAC prescription, except for sex, hypertension, asthma or COPD, history of cerebrovascular accident or transient ischaemic attack and history of bleeding (not statistically significant) and except for history of malignancy, which in itself might be related to NOAC prescription compared with VKA prescription (see Table 2). After multivariable logistic regression analyses with stepwise backward elimination, older age and concurrent heart failure, diabetes mellitus, vascular disease and dementia were independently associated with a higher likelihood of VKA rather than NOAC prescription, whereas hypertension and malignancy were independently associated with a higher likelihood of NOAC rather than VKA prescription (see Table 2). Dementia was most strongly associated with a higher likelihood of VKA rather than NOAC prescription (adjusted odds ratio 2.11, 95%
RkJQdWJsaXNoZXIy MTk4NDMw